A plurality of rechargeable battery systems with lithium polymer batteries are known, which are used to drive various consumers, for example, for driving or energizing solar-powered vehicles, electric automobiles, model airplanes and airplanes, mobile phones, MP3 players and stationary power plant energy storages devices. The lithium polymer battery is a rechargeable energy storage device, whose negative electrode consists of graphite, the positive of lithium metal oxide, and has an electrolyte, which consists of a polymer-based film ranging from solid to gel-like. These components of the battery are manufactured as laminating sheets with a thickness of less than 100 μm as round and flat cells. Since the electrolyte is bound in a gel-like polymer and is not liquid, unlike, for example, in lithium ion batteries, no solid housing is necessary to secure the technical structures. To increase the nominal voltage, these batteries comprise a plurality of series-connected individual cells. Due to the manufacture, the individual cells show fluctuations in capacity and internal resistance. This leads to the possibility that the cells may assume critical charged states during charging and discharging. Thus, there is a risk of deep discharge during discharge, and with the charging of same cutoff voltage is not reached during the joint charging of the cells, which may, in turn, lead to the overcharging of individual cells. In order to avoid these critical states, so-called balancers are installed, which balance out the critical charged states in the individual cells.
However, the lithium polymer batteries have the drawback that they are mechanically, electrically and thermally sensitive. Damage, overcharging, deep discharge, excessively high currents, operation at excessively high or excessively low temperatures and prolonged storage in the discharged state damage or destroy the cell. The batteries may swell and explode on overcharging and ignite in the process. These hazardous properties of the lithium polymer batteries lead to severe airplane accidents especially in case of transportation onboard airplanes. It was determined that the lithium polymer batteries may reach temperatures of up to 600° C. in case of unsuitable packaging and may ignite not only themselves but also the area surrounding them.
Standards have therefore been set up for the aforementioned reasons for the transportation onboard airplanes. Thus, such batteries may only be transported onboard airplanes if their maximum output does not exceed 100 Wh and in special battery packs supplied by the manufacturer or in commercially available special battery packs only. The battery packs for consumer devices contain a protective circuit developed for the particular battery against low voltage and excess current, and the cell and charge management should be integrated in the consumer, and a special lithium polymer battery-charging device must be available.
The user of a consumer device, for example, of an electrically operated mountain bike or of a model airplane, who wants to ride in a foreign country or participate in a competition, will face transportation problems under the conditions described, and these problems can be solved with a great effort only. The lithium polymer batteries can be transported individually in the special packagings supplied by the manufacturer. The battery systems comprising these must be taken apart for this and put together again and electrically connected on the site. This is complicated, time-consuming, and dangerous for a lay person. In addition, not all users have the electrotechnical expertise necessary for this. The batteries may become damaged already during disassembly if the procedure was not performed in a professional manner and properly if contacts are poled incorrectly or short-circuits are generated by contacting wires of opposite poles. This involves not only the risk that the batteries will be destroyed but also the risk that persons may suffer electric shocks hazardous for health. Therefore, transportation as air freight is no longer allowed for the current battery systems as a compact pack.